A Pooled Longitudinal Analysis of Workplace Carpal Tunnel Syndrome Carpal tunnel syndrome continues to be a major source of disability among working persons and a major expense to employers and insurers. Unfortunately, studies of associations between workplace exposures to biomechanical factors and carpal tunnel syndrome have been inconclusive as a result of limitations in design, exposure and outcome ascertainment, and statistical power. Between 2001 and 2008, seven research groups conducted coordinated, multi-year, prospective studies of US production workers and collected detailed subject-level upper-extremity biomechanical exposure information with follow-up symptom assessment, physical examination, and nerve conduction measures. The proposed study will pool the data from these prospective studies to create a large database (N = 3573) of occupational exposure, demographic, covariate and outcome measures across a range of occupations and industries. In addition to allowing for precise estimates of the incidence of CTS among members of a diverse working population, the proposed study will quantify with precision exposure-response relationships between biomechanical risk factors (e.g., force, repetition, Strain Index, Hand Activity Level) and incidence of carpal tunnel syndrome while controlling for important covariates (e.g., age, gender, psychosocial factors, BMI). The study will also evaluate, among those with carpal tunnel syndrome at baseline, the relationship between workplace and personal factors and subsequent changes in hand disability. The results of the proposed analyses will provide employers, employees, public-health agencies and occupational health investigators with quantitative estimates of the associations between CTS and occupational biomechanical factors in order to more effectively guide workplace health and safety prevention programs. PUBLIC HEALTH RELEVANCE: Narrative Carpal tunnel syndrome is an important cause of hand disability among blue collar workers. The purpose of this study is to create the largest database to-date on workplace carpal tunnel syndrome by merging together data from seven prospective studies. Detailed workplace activity information has already been collected by all seven studies. This large database will allow us to examine, in detail, the relationships between specific types of hand activity and the chance for developing carpal tunnel syndrome. The study can answer the question of whether how fast the hand moves is more or less important for the development of carpal tunnel syndrome than the amount of grip force applied during a work task. This information is needed by employers, employees, and health and safety personnel to design safer workplaces in order to reduce the chance of developing carpal tunnel syndrome.